Home>Discussions>ELECTRICAL & LIGHTING>How do I track down the sequence of receptacles on a circuit?
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CJR
How do I track down the sequence of receptacles on a circuit?

Long-time lurker, first time poster. :)

I was replacing the drywall on the ceiling of a room this past weekend, when I discovered the end of a live wire tucked into bracing between the joists. Surprise! I didn't hit it with metal or get shocked, but I sure wasn't expecting to see it there...

I have figured out which circuit it's on, but whoever wired this house had a pretty creative approach, and the circuit winds its way over half the house, so the fact that the wire heads in a particular direction isn't helping me much. (It's obviously at the end of the run though.)

While I have the ceiling open, I'd really like to track down what the other end of this wire is connected to and disconnect it right, but is there any other approach apart from disassembling each fixture or receptacle on the circuit to see where it's being fed from?

I may end up doing that, but it'll take a minimum of a half-day to disassemble each outlet, run downstairs to re-power it and test each wire coming into the box. Is there any other approach?

Would I be completely terrible if I stagger-cut and taped the ends, wire-nutted it off and put it in a proper box mounted on one of the joists above the ceiling?

A. Spruce
Re: How do I track down the sequence of receptacles on a circuit?
CJR wrote:

Would I be completely terrible if I stagger-cut and taped the ends, wire-nutted it off and put it in a proper box mounted on one of the joists above the ceiling?

The easiest way to terminate the wire will be to put it into a box that is accessible within the attic. You want to cap each wire before folding them down into the box and installing a cover. You don't need to stagger cut the wires or tape them, just cap them so that no conductor is showing and tuck them into the box.

If you want to go to the trouble of finding the last fixture to terminate it at, that will likely be the closest fixture to the abandoned wire that shares the same circuit.

jled96
Re: How do I track down the sequence of receptacles on a circuit?

If you cannot find the feed for the abandoned line you must keep it in an accessable box, either from above or below, most time when i run into this situation is when there was a ceiling fixture with a constant feed and no switch,if you have the ceiling open you could notch the top plate of a nearby wall and pull the cable down into the wall and terminate it in an old work box and either add a receptacle, or cap it off and use a blank cover. You could also add a light/fan box while you have the ceiling open and add a switch,dimmer/fan speed control to a nearby wall and utilize your existing line if you need additional lighting, if not the just cap it off and keep it accessable. Good Luck!

CJR
Re: How do I track down the sequence of receptacles on a circuit?
A. Spruce wrote:

The easiest way to terminate the wire will be to put it into a box that is accessible within the attic.

That's the problem - this box would have to be tucked in an inaccessible spot between two floors and covered by ceiling. It's technically not a splice in a wall if it just terminates I suppose...

Is there a detector that's good enough to trace a live wire behind drywall or plaster so I can try to get a guess at where this wire heads?

I tried the two nearest fixtures to the live wire, but struck out in both cases.

HoustonRemodeler
Re: How do I track down the sequence of receptacles on a circuit?

Try waiting until late at night when its very quiet and jiggling the wire to listen for where it heads off to.

A. Spruce
Re: How do I track down the sequence of receptacles on a circuit?
CJR wrote:

That's the problem - this box would have to be tucked in an inaccessible spot between two floors and covered by ceiling. It's technically not a splice in a wall if it just terminates I suppose...

Is there a detector that's good enough to trace a live wire behind drywall or plaster so I can try to get a guess at where this wire heads?

I tried the two nearest fixtures to the live wire, but struck out in both cases.

Sorry, I missed that part in your original post. In this case you'd leave the box accessible in the ceiling with a blank cover. The other option would be to follow the advice of moving the wire into the wall or turning it into a light fixture.

I don't know if there is a line detection device to ferret out how a wire is run. You may have missed my description of how to locate the nearest device. If you have isolated the circuit that it is on, you then map that circuit, which should be fairly easy.

I have mapped circuits on more than one occasion by shutting off everything in the panel but one circuit, then I diagram the house on a piece of paper, marking all switches, outlets, etc. and go through the house room by room with an outlet tester or wiggy and check each outlet and light switch, noting on your diagram what is live. Repeat this process for each breaker in the panel and you will have mapped your house. I like to use a different color pen/pencil for each circuit to make reading the diagram quick and easy.

This map should tell you exactly where every device is that is on the same circuit as the rogue wire. From there you should be able to deduce where to terminate it at it's source. I recall you saying that the previous owner did some "creative" wiring. If they were particularly creative, they may have buried a junction box somewhere that you will never find.

Mastercarpentry
Re: How do I track down the sequence of receptacles on a circuit?

There are gadgets for this that use an electronic tone injected into a circuit to let you find where the tone turns up downstream. These are available through Harbor Freight and any electrical supplier. IIRC one brand is called "Circuit Detective". Essentially they clip onto the downstream side of a breaker and have a 'detector' that is used at any terminus. Some will allow you to follow the tone through a closed wall. Can't recall what they cost, the cheap ones are around $40 IIRC but I don't think they trace through walls.

Were it me I wouldn't want to add a draw on that circuit till I knew what else was on it and that it could handle it. If you can figure out were it feeds from, maybe you can cut it there and enclose it properly at that location. Or you can use it to feed a Smoke Detector which draws almost nothing and will not look so out of place on a ceiling!

Phil

CJR
Re: How do I track down the sequence of receptacles on a circuit?

I think we may have a winner on the smoke detector! The room will have wall sconces in it, so a ceiling fixture would have looked sort of stupid, but come to think of it, putting a smoke detector up there is a good idea.

This weekend while the wife and kids are out, I'm going to try a few more fixtures to see if I can isolate where it's fed from. If I strike out, I'm declaring victory with a smoke detector and moving on with my life.

jled96
Re: How do I track down the sequence of receptacles on a circuit?

That is a great idea with the smoke detector, could do co detector also or a combo unit, just had an elderly customer have me add automatic LED lights in a few rooms so she could see at night without waking her daughter, also use almost no energy. Good Luck!

William
Re: How do I track down the sequence of receptacles on a circuit?
CJR wrote:

is there any other approach apart from disassembling each fixture or receptacle on the circuit to see where it's being fed from?

Simple answer is yes, simply use a wire tracer. Home depot has one for less than 40 bucks. You can see it here. Harbor Freight has one for only 17 bucks here. I'm going to buy the one at Harbor Freight tomorrow and compare it to the one from HD. It appears the one from Harbor Freight has a headphone jack, which is nice for noisy environments, but the manual makes no mention of it. It will pay for itself the first time you use it. Simply hook one end to the wire you found buried, and then go to your panel and it will tell you which is the other end. Then simply disconnect it.... ;)

William
Re: How do I track down the sequence of receptacles on a circuit?

I just bought the one from Harbor Freight and amazingly it is actually nicer than the Sperry that I got from Home Depot for three times the price (the HF unit is only 12.99 with 25% off coupon), Plus the HF unit is easier to use, has a headphone jack (nice for when using in noisy environments) and it's also got a much better speaker plus it comes with a storage case. This little gem will pay for itself the first time that I use it. Every home owner should have one of these in their toolbox. This will also be a time saver when tracing wires in a car :)

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